Entamoeba histolytica life cycle. Diagram showing the life cycle of the parasitic amoeba Entamoeba histolytica, cause of the intestinal infection amoebiasis in humans. Amoebiasis occurs through the ingestion of food and water contaminated by faeces that contain Entamoeba histolytica cysts. Most people infected by Entamoeba histolytica do not show symptoms. However, when the parasite causes inflammation of the intestines, symptoms include diarrhoea and severe abdominal pain. Amoebiasis is treated by using antibiotics to kill the amoeba and antimicrobial medicine to kill the cyst.